A variety of inkjet recording devices (inkjet printers) configured to eject an ink from nozzles of an inkjet head (recording head) and to record (print) desired character and figure on a recording medium have been known.
In the inkjet recording device, a variety of conveyance mechanisms configured to convey the recording medium have been adopted. For example, a belt conveyance mechanism has a configuration where a flexible endless belt configured to convey a medium such as a fabric, and a sheet is put on a pair of rollers, the rollers are rotated to move the belt by a driving motor and the recording medium is thus conveyed.
As another example, when a roll-shaped recording medium is used, the roll-shaped recording medium is fed from a feeding roller and is conveyed with being wound on a winding roller without using a belt for conveyance.
In the belt conveyance, regarding an actual movement amount (feed amount) of the belt, a deviation from a designated feed amount occurs due to the eccentricity of the roller and the non-uniformity in a thickness of the belt. Therefore, a technology of providing a rotary encoder configured to detect rotation of the roller, detecting an actual movement amount and correcting a driving signal of the motor by a detection signal thereof has been suggested.
For example, a belt device disclosed in Patent Document 1 has been known as the technology of correcting the eccentricity variation of the roller and the thickness variation of the belt upon the conveyance of the recording medium. The belt device includes a first roller, which is a driving roller, a second roller, which is a driven roller, an endless belt put between the first roller and the second roller, and a facing roller provided to face the first roller with the belt being interposed therebetween. The first roller and the facing roller are respectively provided with rotary encoders. According to this configuration, the thickness variation of the belt and the eccentricity variations of the first roller and facing roller, which are detected by the rotary encoders provided for the first roller and the facing roller, are stored, and the driving signal of the driving motor is corrected on the basis of the variation components thus recorded, so that the first roller is rotated to reduce the variation in a moving speed or movement distance of the belt.